The table shows the gender of students in each year group in a school

Question

Year: 7 8 9 10 11

Male: Year 7 = 71, Year 8 = 92, Year 9 = 108, Year 10 = 96, Year 11 = 93

Female: Year 7 = 89, Year 8 = 88, Year 9 = 90, Year 10 = 92, Year 11 = 100

A) What is the probability that a student chosen at random is a boy in Y10?

B) What is the probability that a girl chosen at random is in Y8?

Answer 1

(A) Of the 919 students (total incl boys & girls), 96 are boys in year10. Assuming that each student has an equal chance of being selected, P(boy in Y10) = 96/919 ≈ .104. So, about 10%

(B) Of the 459 girls at the school, 88 are in year 8. Assuming that each girl has an equal chance of being selected, P(girl is in Y8) = 88/459 ≈ .192. So, about 19%